The present invention relates to a central steam humidifier of the type in which steam is injected by nozzles in a distribution manifold or manifolds into the interior of a heating duct or the like. Humidifiers of this type are exemplified by U.S. Pat. Nos. 3,386,659; 3,642,201; 3,857,514; and 3,923,483 and certain known commercial prior art, and it is the objective of this invention to improve on the prior art, particularly with relation to the means for returning liquid condensate from the steam distribution manifold to a drain leading to a condensate trap.
In much of the prior art, condensate return tubing external to the steam separator and connected to the far end of the distribution manifold is employed. Such arrangements are costly and significantly increase the complexity of piping or tubing required for the humidifier.
More particularly, in accordance with the present invention, condensate from the steam distribution manifold is directed into the discharge chamber of the steam separator for passage into a drain line near the outlet of the separator at a point downstream from the needle valve of the separator. A common coupling is utilized to secure the steam distribution manifold and a condensate baffle contained therein in assembled relationship with the steam separator.
In other prior art humidifiers, condensate return tubing is contained within the body of the distribution manifold and leads to a drain connection outside of the separator unit. This relatively complicated arrangement is also avoided by the present invention.
A distinct advantage over the prior art possessed by the invention due to returning the condensate into the separator is the ability of the system to vaporize some of the condensate before delivering it to the drain pipe, thus avoiding loss of valuable energy.
Other objects and advantages of the invention will become apparent during the course of the following description.